Delivery control for fuel injector pumps



April 4, 1950 G. w. BAIERLEIN DELIVERY comm. Foa FUEL mJEc'ron Pumps 2 Sheets-Sheet 1 O'iginal Filed Feb, 27, 1946 April 4, 195o G. BAIERLEIN DELIVERY CONTROL FOR FUEL INJECTOR PUMPS 2 Sheets-Sheet 2 Original Filed Feb. 27, 1946 FIG.2

to the mounting plate I0.

Patented Apr. 4, 1950` DELIVERY CONTROL FOR FUEL INJECTOR PUMPS George W. Baierlein, Springfield, Mass., as'signor to Niles-Bement-Pond Company, West Hartford, Conn., a corporation of New Jersey Original application February 27, 1946, SerialNo. 650,408. Divided and this application February 6, 1947, Serial No. 726,845

9 Claims.

The present application is a division of my application Serial No. 650,408, led February 27, 1946, now Patent Number 2,455,289, issued November 30, 1948.

The present invention relates to fuel injection pumps for internal combustion engines. Certain of the features of the invention are of particular utility in connection with a pump for a multiple cylinder engine having a plurality of pump plungers, one for each cylinder. Other features of the invention are of especial utility in connection with an injection pump adapted for use on an aircraft engine, wherein light weight is very important. An object of the present invention is to provide improved mechanism for varying simultaneously the delivery of all the plungers in a multiple plunger pump.

Another object is to provide improved mechanism for adjusting individually the delivery of each of the pump plungers.

A further object is to provide such individual Figure 3 is a plan veiw of a part of the plunger adjusting mechanism, and Y Figure 4 is an elevational view of the part shown in Figure 3, rotated thru 90 from the position of Figure 3.

Referring now to the drawings, there is shown a pump mechanism consisting of a. mounting plate I 0, which is provided with a iiange I2,

having holes I4 bored thru it to receive bolts (not shown) so that it may be mounted on a suitable pad provided on an internal combustion engine. A pump body. I6 is attached, by any suitable means such as dowel studs I8 (Figure 2l, A drive shaft 20 is carried inthe plate I0 by a combined radial and thrust ball bearing 22 and by 'a needle bearing 2 nism to be described in detail below, a plurality of pump plungers 30, which reciprocate in barrels 32 received in bores 34 thru the housing I6. A cover 36 is provided for the pump. This cover is attached, by means of bolts 38 and dowel pins 46 (Figure 2) to the pump body I6.

The end of pump barrel 32 nearest the plate I0 is closed by a 4valve seat member 42. This seat member is provided with a passage thru its central portion, and a valve 44 engages the face of the seat member on the side opposite the barrel 32. A spring 46 biases the valve 44 to closed position. The spring 46 is held by a retainer 48 threaded into the plate I0. Washers 50 and 52 and a spacer 54 separate the rim of the retainer 48 from the rim of seat member 42. When the retainer 48 is threaded in place, it holds the washers 50 and 52, the spacer 54, the seat mem-- ber 42, and the barrel 32 in assembled lrelation, forcing a shoulder 56 on the barrel 32 up against a corresponding shoulder in the pump body I6. The spacer 52 is provided with lateral outlet passages- 58, leading to a drilled passage 60 which opens rinto the bolt hole I4. From there the fuel discharged by the pump may be conveyed thru a hollow bolt, in a well-known manner, to one of the cylinders of the engine.

The outer surface of each of the barrels 32 is provided with a recess 33. A set screw 35, carried by the body I6 engages the recess 33 and holds the barrel against rotation in the body I6, so that the calibration of the pump cannot be disturbed by any change in the angular position of port i34.

The outer race of bearing 22 is press-fitted into the plate I0. The inner race is held against a shoulder on the shaft 20 by a lock nut 62 and a lock washer 64. It may be seen that the thrust forces on the bearing 22 are such as to tend to move theshaft 20 downwardly thru the plate IIJ. Therefore these thrust forces tend to hold the outer race of bearing 22 more rmly in its seat.

The inner race of bearing 26 is held in place against a shoulder on shaft 20 by a lock nut 66 and a lock washer 68. A timing disc 'I0 is clamped between the lock washer 68 and the inner race of bearing 26. The purpose of the timing disc 10 willA be later described. The outer race of the bearing 26 is retained in the wobble plate 28 by a retaining ring 12, which may be of the wellknown snap ring type.

Each of the plungers 36 is connected by means of a shear pin 'I4 to a push rod 16. The lower end of push rod 'I6 terminates in a ball 18. The

3 wobble plate 28 is provided on its .peripheral surface with a groove 80, wide and deep enough to receive the balls 18. The groove 80 separates an upper, as it appears in the drawing, flange 82 on the wobble plate from a lower flange 84. The upper flange 82 has its outer edge slotted, as at 86, so that the push rods 16 may be passed thru the slot during assembly. Each ofthe slots 86 opens into a generally circular aperture 88, which allows for the wobbling motion of the wobble plate 28 with respect to the push rods 16. Each of the balls 18 rides in a pair of upper and lower shoes 90 and 92, which are received with the ball in the groove 80. The upper shoe 90 is provided with a suitable central aperture to permit passage of the push rod 1 6 therethru. It may be seen that as the shaft 20 rotates a wobbling motion is imparted to the plate 28 so that the plungers 30 and push rods 16 are sequentially reciprocated. It may also be seen that the thrust forces acting parallel to the shaft 20, dueto the fluid pressures built up by the plungers, are all carried by the plungers 30, the associated structure which connects the plungers to the wobble plate, the wobble plate 28, and shaft 20 to the bearing 22 and the mounting plate I0. The body I6 is Xed at one end to the mounting plate I0. No other part of the body I6 is attached to any fixed part of the engine. Thrust forces reaching the plate l are not transmitted thru the body I6, because there can be no opposing reactive forces. Hence the body I6 cannot be stressed by such thrust forces. Therefore, it is possible to build the body |6 of a light, relatively weak metal such as aluminum, while the parts subject to stress are m-ade of stronger metal, such as steel. In this way it has been found possible to substantially reduce the weight of the multiple pump unit. Where such a pump unit is intended for use in an aircraft, such a reduction in weight is tremendously important. It should be noted that the flange 82, which transmits thrust to the plungers on their intake strokes, is made lighter than the ilange 84, which transmits thrust to the plungers on their pumping strokes. This difference in the thickness of the two flanges also contributes to the reduction of the weight of my pumping mechanism.

Each plunger' 30, carries a sleeve 94, whose structure is shown in detail in Figures 3 and 4.

The sleeve 94 consists of a generally tubular portion 96. The portion 96 is slotted as shown at 98 from one side laterally across for a distance of more than half its diameter. The part of the sleeve 94 below the slot 98 is provided with a longitudinal slot as shown at |09, which separates that portion of sleeve 96 into two ngers |02, |04. These two fingers are provided at their free ends with lugs |06, |08. A tapered screw ||0 is provided for joining the two lugs. It may be seen that upon tightening of the screw ||0 the two fingers |02 and |04 are tightly clamped on the surface of the push rod 16, so that the sleeve 94 and the push rod 16 and the plunger 30 rotate together. When the screw ||0 is loosened, it is possible to rotate the push rod 16 within the sleeve 94 Without rotating the later. The sleeve 94 is provided with a pair oi upwardly extending projections I2 which mate with corresponding projections `||4 on a sleeve ||6 which surrounds the barrel 32. The sleeve ||6 carries a pinion gear ||8 having teeth over at least a 90 sector thereof. All of the pinion gears I I8 engage a central ring gear |20 carried on a projecting hub portion of the pump body I6. The toother portions of the pinion gears ||8 all face inwardly so as to engage the ring gear |20.

One of the sleeves ||6 is also provided, on the portion of its periphery nearest the outside of the casing, with a bevel gear sector |22. This engages with another bevel gear sector |24 carried by a control shaft |26 mounted in a suitable hub |28, which is carried by the pump body I6. Outside the body I6, the control shaft |26 is splined, as shown at |30 and thereby provided with means by which it may be rotated from the outside of the pump unit.

Each of the pump plungers is provided with a helical scroll |32 of gener-ally conventional form, which cooperates with an inlet port |34. When the port |34 is closed by the scroll |32, then the plunger is actively pumping fuel thru the discharge valve 44. Each .plunger is also provided. below the scroll |32, with a circumferential groove |33. As soon as the port |34 is uncovered by the upper edge of groove |33, then the pressure ahead of the plunger is relieved and pumping ceases. By rotating the plunger on its own axis, the length of the period during which pumping takes place may be varied, thereby Varying the fuel delivery per stroke of the pump plunger. By operation of the control shaft |26, all the plungers may be simultaneously rotated. Rotation of control shaft |26 causes one pinion gear |I8 to be rotated and this motion is transmitted thru the ring gear |20 to all the other pinion gears. If it is desired to adjust the delivery per stroke of one of the plungers, without affecting'the others, it is only necessary to remove the cover 36 whereupon the clamping screws ||0 associated with all the plungers become accessible.

The timing disc 10 cooperates with a timing pins |36 so that it is possible to determine the angular position of the pump shaft from the out side of the casing. The periphery of the disc 10 is slotted as shown at I 3B. The timing pin |36 is mounted in a cup |40 carried by the cover 36. A spring |42 in the cup |40 biases the pin to the position shown in Figure l where it does not engage the slotl |36 or the timing disc d0. A cover |44 is provided for the outer end of the timing pin so that it will not be accidentally pushed in while the pump is in operation. When it is desired to determine the angular position of shaft 20 for timing the pump to the engine, the cover |44 is removed and the pin |36 is depressed and held in. The shaft 20 may then be slowly rotated by hand until the pin is felt to drop into the slot |38. The slot |38 is located in the timing disc 10 so that its angular position corresponds to the end of delivery by the pump plunger serving cylinder No. l of the engine.

The driving end of shaft 20 is driven thru an intermediate drive member |46, which corrects for misalignment between the pump shaft 20 and the engine drive shaft.

The shaft |26, outside the body |6 may be provided with a suitable pointer cooperating with a scale |52, to indicate the pump delivery setting.

F'uel is supplied to the pump thru an inlet connection |54 which leads to a chamber |56 surrounding all the barrels 32 at a. point near their inlet ports |34.

Oil is supplied under pressure thru a connection indicated generally at |58 to the chamber |60 formed between the cover |56 and the pump body ||6. The oil flows from the chamber |60 thru a check valve |62 and thence out thru the hollow center of the shaft 20. This lubricating system is completely shown and claimed in the co-pending application of Milton E. Chandler, Serial No. 609,350, 'flied August 7, 1945, now Patent Number 2,423,373, issued July 1, 1947, and forms no part of the present invention.

The terms and expressions which I have employed are used as terms of description and not of limitation, and I have no intention, in the use of such terms andv expressions, of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

I claim as my invention:

1. Injector pump mechanism comprising a generally cylindrical housing, a plurality of pump barrels in said housing arranged parallel to and equidistant from the axis of said housing, a plurality of plungers, one plunger being reciprocable in each of said barrels, means for reciprocating said plungers, means associated with each said plunger for varying the fluid delivery per stroke thereof upon rotation of said plunger about its own axis, a pinion gear attached to each of said plungers for concurrent rotation therewith, a master gear mounted coaxially within said housing and engaging all said pinion gears, a control shaft extending thru one wall of said housing, a gear on said control shaft inside said housing engaging one of said pinion gears for concurrent rotation therewith, so that upon rotation of said control shaft gear, said one pinion gear also rotates and drives said master gear and thereby all the other pinion gears, and means on said shaft outside said housing for rotating said shaf t and thereby simultaneously varying the delivery per stroke of all said plungers.

2'. Injector pump mechanism, comprising a generally cylindrical housing, a plurality of pump barrels in said housing arranged parallel to and equidistant from the axis of said housing, a plurality of plungers, one plunger being reciprocable in each of said barrels, means for reciprocating said plungers, means associated with each said plunger for varying the fluid delivery per stroke thereof upon rotation of said plunger about its own axis, a sector gear attached to each of said plungers for concurrent rotation therewith, a hub mounted centrally of said housing, a master gear mounted on said hub and engaging all said sec.

tor gears, a control shaft extending thru one wall of said housing, means on said control shaft inside said housing for rotating one of said sector' gears, and means on said control shaft outside said housing for rotating said shaft and thereby simultaneously varying the delivery per stroke of all said plungers.

3. Injector pump mechanism, comprising a generally cylindrical housing, a plurality o f pump barrels in said housing arranged parallel to and equidistant from the axis of said housing, a plurality of plungers, one plunger being reciprocable in each of said barrels, means for reciprocating said plungers, means associated with each said plunger for varying the fluid delivery per stroke thereof upon rotation of said plunger about its own axis, a sector gear attached to each of said plungers for concurrent rotation therewith, a hub mounted centrally of said housing, a master gear mounted on said hub and engaging all said sector gears, a control shaft extending thru one wall of said housing, a rst bevel gear on said control shaft inside said housing, a second bevel gear engaging said first gear and movable concurrently with one of said pinion gears, and means on said control shaft outside said housing for rotating said control shaft and thereby simultaneously varying the delivery per stroke of all said plungers.

4. Injector pump mechanism comprising a generally cylindrical housing, a plurality of pump barrels in said housing arranged parallel'to and equidistant from the axis of said housing, a plurality of plungers, one plunger being reciprocable in each of said barrels, means for reciprocating said plungers, means associated with each said plunger for varying the fluid delivery per stroke thereof upon rotation of said plunger about its own axis, a pinion gear attached to each of said plungers for concurrent rotation therewith, a master gear mounted coaxially within said housing and engaging all said pinion gears, a control shaft extending thru one wall of said housing in a direction generally perpendicular to said axis, means on said control shaft inside said housing for rotating one of said gears, and means on said control shaft outside said housing for rotating said control shaft and thereby simultaneously varying the delivery per stroke of all said plungers.

5. Injector pump mechanism, comprising a cylinder, a plunger reciprocable in said cylinder, means associated with said plunger for varying the iiuid delivery per stroke thereof upon rotation of said plunger about its own axis, delivery control meansfor rotating said plunger including a gear encircling said cylinder, a first sleeve surrounding said plunger, a second sleeve attached to said gear, complementary projections on said sleeves for producing concurrent rotation thereof about the axis of said plunger while permitting relative reciprocation of said sleeves, said first sleeve comprising a tubular member having a lateral slot extending from one side thereof more than half way toward the diametrically opposite side to separate said member into two portions and a longitudinal slot thru one of said portions at said one side to separate said one portion into two arcuate lingers attached to said opposite side, a lug formed on the end of each of said fingers, and screw means connecting said lugs and effective upon tightening thereof to clamp said fingers against said plunger so that said sleeve vand said plunger rotate together, said screw means being effective upon loosening thereof to unclamp said fingers so that said plunger may be rotated relative to said sleeve and said gear to calibrate said delivery control means.

6. Injector pump mechanism, comprising a cylinder, a plunger reciprocable in said cylinder, means associated with said plunger for varying the uid delivery per stroke thereof upon rotation of said plunger about its own axis, delivery control means for rotating said plunger including a gear encircling said cylinder, a rst sleeve surrounding said plunger. a second sleeve attached to said gear, complementary projections on said sleeves for producing concurrent rotation thereof about the axis of said plunger while permitting relative reciprocation of said sleeves, said rst sleeve comprising a tubular member having a lateral slot extending from one side thereof more than half way toward the diametricalv opposite side to separate said member into two portions and a longitudinal slot thru one of said portions at said one side to separate said one portion into two arcuate ngers attached to said opposite side, and means for moving the ends of said fingers toward and away from each other to clamp said fingers against said plunger so that said sleeve and said plunger rotate together, or to unclamp said fingers so that said plunger may bc rotated relative to said sleeve and said gear to calibrate said delivery control means.

7. Injector pump mechanism, comprising a generally cylindrical body having a plurality of bores therethru parallel to the axis thereof, a plurality of pump plungers, one plunger being reciprocable in each of said bores, mounting means on one end of said body, a. generally cup-shaped cover for the other end of said body, said cover and said body enclosing achamber, a drive shaft extending coaxially thru said body from said one end into said chamber, means attached to said shaft in said chamber for reciprocating said plungers. means associated with each of said plungers and accessible from said chamber for varying the delivery per stroke thereof, means for simultaneously operating al1 said delivery varying means, and means in said chamber for disconnecting each delivery varying means from said operating means to permit individual adjustment of said delivery varying means, said disconnecting means being accessible for such adjustment upon removal of said cover.

8. Injector pump mechanism, comprising1 a generally cylindrical body having a plurality of bores therethru parallel to the axis thereof, a plurality of pump plungers, one plunger being reciprocable in each of said bores, mounting means on one end of said body, a generally cup-shaped cover for the other end of said body, said cover and said body enclosing a chamber, a drive shaft extending coaxially thru said body from said one end into said chamber, means attached to said shaft in said chamber for reciprocating said plungers, means associated with each of said plungers and operable from said chamber for varying the delivery per stroke thereof, means in said chamber for simultaneously operating all said delivery varying means, and means in said chamber for disconnecting each delivery varying means from said operating means to permit individual adjustment of said delivery varying means, said disconnecting means and said oper- Number Name Date 1,842,569 Richer Jan. 26, 1932 2,160,735 Hoffer May 30, 1939 2,215,827 Ditto Sept. 24, 1940 2,333,698 Bremser- Nov. 9, 1943 2,380,574 Beeh et al. July 31, 1945 2,388,462 Beeh Nov. 6, 1945 2,400,119 Joy May 14, 1946 2,423,373 Chandler July 1, 1947 2,428,408 Beeh Oct.4 7, 1947 2,455.289 Baierlein Nov. 30,

8 ating means being accessiblevupon removal of said cover.

9. Injector pump mechanism, comprising a generally cylindrical housing, a plurality of pump barrels in said housing arranged parallel to and equidistant from the axis of said housing, a plurality of plungers, one plunger being reciprocablc in each of said barrels, means for reciprocating said plungers, means associated with each said plunger for varying the fluid delivery per stroke thereof upon rotation of said plunger about its own axis, a pinion gear attached to each of said plungers for concurrent rotation therewith, a master gear mounted coaxially within said housing and engaging all said pinion gears, a control shaft extending thru one wall of said housing in a direction generally perpendicular to said axis, a first bevel gear on said control shaft inside said housing, a second bevel gear engaging said first bevel gear and attached to one of the other gears within said housing for concurrent rotation therewith, and means on said control shaft outside said housing for rotating said control shaft and thereby simultaneously varying the delivery per stroke of all said plungers.

f GEORGE W. BAIERLEIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

